Pouch battery gas pocket prefabricated sealing structure and production method thereof

Abstract

The application provides a soft package battery gas bag prefabricated sealing structure and a production method thereof, and belongs to the technical field of battery manufacturing. The gas bag is provided with a containing cavity. A separation belt is arranged in the gas bag. The separation belt comprises reinforced portions and weak portions. The weak portions are arranged in the gaps between two adjacent reinforced portions and connect the two adjacent reinforced portions or are arranged between the reinforced portions and the edges of the gas bag and connect the reinforced portions and the edges of the gas bag. The reinforced portions and the weak portions jointly separate the containing cavity into a battery core cavity and a liquid supplement cavity. The mechanical strength of the weak portions is lower than that of the reinforced portions. The application has the beneficial effect that the separation belt composed of the reinforced portions and the weak portions is processed in the gas bag, the containing cavity is pre-separated into the battery core cavity and the liquid supplement cavity, the weak portions are preferentially controllable to break when an opening force is applied, and the electrolyte in the liquid supplement cavity is completely released into the battery core cavity at one time.

Description

Technical Field

[0001] This invention belongs to the field of battery manufacturing technology and relates to a pre-sealed structure for a soft-pack battery air bag and its production method. Background Technology

[0002] In the manufacturing process of lithium-ion pouch batteries, a secondary electrolyte injection process is often used to compensate for electrolyte consumption during formation and cycling, thereby improving cycle life, capacity retention, and overall electrochemical performance. This process involves injecting additional electrolyte after the initial electrolyte injection and formation to optimize the stability of the electrode / electrolyte interface. However, existing secondary electrolyte injection technologies still have significant shortcomings in terms of safety, process controllability, and sealing reliability.

[0003] One of the mainstream methods for secondary electrolyte injection is to manually cut open the gas bag or aluminum-plastic film seal while the battery is formed and charged, inject secondary electrolyte, and then vacuum heat seal it. This method poses serious safety hazards: since the battery is already charged, if the tool comes into contact with the positive and negative electrodes or internal structures during the operation, it can easily cause a short circuit or even thermal runaway; at the same time, the cutting process can easily generate aluminum-plastic film debris, which may fall into the cell and cause micro-short circuits, and the opening exposed to the environment can introduce moisture, leading to electrolyte decomposition, gas generation, and damage to the SEI film, seriously affecting battery performance and lifespan.

[0004] Another common approach is to pre-fabricate an independent replenishment chamber on the gas bag via heat sealing before or during the initial electrolyte injection, and pre-inject secondary electrolyte. After formation, external force is applied to this chamber to rupture the weak points, thereby releasing the electrolyte. However, this structure relies on the heat sealing process to create areas of varying mechanical strength—typically achieved by adjusting the heat sealing width or temperature to create these "weak points." But the inner layer of the aluminum-plastic film is made of CPP (cast polypropylene), and the heat radiation diffusion effect during heat sealing makes it difficult to precisely control the actual melting width of the weak points. The mechanical strength of the weak points fluctuates significantly between different batches, and even within the same batch, resulting in inconsistent extrusion pressure required for opening: insufficient pressure will prevent the opening, while excessive pressure may damage the normal sealing area or the aluminum-plastic film itself, causing leakage or battery cell failure.

[0005] In summary, existing secondary injection technologies either pose risks of contamination and safety due to external punctures, or result in uncontrollable opening due to unstable heat-sealing processes at weak points. They are difficult to balance safety, reliability, and mass production consistency, and therefore have significant room for improvement. Summary of the Invention

[0006] The purpose of this invention is to address the aforementioned problems in the prior art by proposing a pre-sealed structure for a soft-pack battery gas bag and its production method.

[0007] The objective of this invention can be achieved through the following technical solution: a pre-sealed structure for a soft-pack battery gas bag, comprising: An air bag, which has a receiving cavity; A separating band is located in the air bag. The separating band includes a reinforcing section and a weak section. The weak section is located in the gap between two adjacent reinforcing sections and connects the two adjacent reinforcing sections. The reinforcing section and the weak section together divide the receiving cavity into a cell cavity and a liquid replenishment cavity. The mechanical strength of the weak section is lower than that of the reinforcing section. When an opening force is applied, the weak section breaks first before the reinforcing section. When the weak part breaks, the cell cavity is connected to the electrolyte replenishment cavity, so that the electrolyte in the electrolyte replenishment cavity flows into the cell cavity.

[0008] In the above-mentioned pre-sealed structure of a soft-pack battery gas bag, a liquid replenishment sealing strip is also included. The liquid replenishment sealing strip is located in the gas bag. The two ends of the weak part are respectively connected to one end of the two reinforcing parts, and the other end of the reinforcing parts is connected to the edge of the gas bag. The reinforcing parts, the weak part, and the liquid replenishment sealing strip surround to form the liquid replenishment cavity, or the reinforcing parts, the weak part, the liquid replenishment sealing strip, and the edge of the gas bag surround to form the liquid replenishment cavity.

[0009] In the above-mentioned pre-sealed structure of a soft-pack battery gas bag, the end of the reinforcing part and the end of the weak part partially overlap to form a leak-proof part.

[0010] In the above-mentioned pre-sealed structure of a soft-pack battery gas bag, the reinforcing part is the heat-sealed area formed during the heat-sealing process of the gas bag.

[0011] In the above-mentioned pre-sealed structure of a soft-pack battery gas bag, the weak part is the ultrasonic welding area formed during the ultrasonic welding process of the gas bag.

[0012] In the above-mentioned pre-sealed structure of a soft-pack battery gas bag, the gas bag is further provided with a punching section, which is a punching area formed by the gas bag during the punching process, and the punching section is located in the liquid replenishment chamber.

[0013] Secondly, a method for producing a pre-sealed structure for a soft-pack battery bag, applied to the aforementioned pre-sealed structure for a soft-pack battery air bag, includes the following steps: S1: Inject liquid into the air bag once; S2: After one injection is completed, the weak part is formed at the first reserved position, so that at most one end of the weak part is connected to the edge of the air bag; S3: The reinforcing part is formed at the second reserved position, so that the end of each weak part that is not connected to the edge of the air bag is connected to the edge of the air bag through the reinforcing part, thereby dividing the receiving cavity into the cell cavity and the liquid replenishment cavity; S4: Inject secondary electrolyte into the replenishment chamber through the opening of the replenishment chamber; S5: Process to form the replenishment sealing strip to seal the opening of the replenishment cavity.

[0014] In the above-mentioned method for producing a pre-sealed structure for a soft-pack battery bag, in step S2, the first reserved position of the air bag is ultrasonically welded to form the weak part.

[0015] In the above-mentioned method for producing a pre-sealed structure for a soft-pack battery bag, in step S3, the second reserved position of the air bag is heat-sealed to form the reinforcing part.

[0016] In the above-mentioned method for producing a pre-sealed structure for a soft-pack battery bag, in step S3, the first reserved position and the second reserved position partially overlap, so that when the reinforcing part is formed in the second reserved position, the end of the reinforcing part partially overlaps with the end of the weak part, thereby forming a leak-proof part.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: By forming a separating zone composed of a reinforced part and a weak part inside the air bag, the receiving cavity is pre-divided into a cell cavity and a replenishment cavity. Utilizing the characteristic that the mechanical strength of the weak part is lower than that of the reinforced part, the weak part is preferentially and controllably ruptured when an opening force is applied, achieving a one-time complete release of electrolyte from the replenishment cavity to the cell cavity. This structure avoids additional breaking tools or complex triggering mechanisms, simplifies the secondary liquid injection activation operation, and ensures that the reinforced part maintains its sealing integrity during use, preventing electrolyte leakage. By partially overlapping the ends of the reinforced part and the weak part to form a leak-proof section, the electrolyte is effectively prevented from seeping through the gap between the reinforced and weak parts, significantly improving the reliability and leak-proof performance of the sealing structure. The weak part is set as an ultrasonic welding area, and by precisely controlling the ultrasonic welding parameters, a weak connection area with mechanical strength lower than that of the heat-sealed reinforced part is formed. This method requires no additional materials, has strong process compatibility, and allows for precise control of the rupture threshold, achieving reliable and consistent opening performance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the pre-sealed structure of the soft-pack battery gas bag according to Embodiment 1 of the present invention.

[0019] Figure 2 for Figure 1 Enlarged view of part A.

[0020] Figure 3 This is a schematic diagram of the pre-sealed structure of the soft-pack battery gas bag according to Embodiment 2 of the present invention.

[0021] Figure 4 This is a schematic diagram of the pre-sealed structure of the soft-pack battery gas bag according to Embodiment 3 of the present invention.

[0022] Figure 5 This is a schematic diagram of the pre-sealed structure of the soft-pack battery gas bag according to Embodiment 4 of the present invention.

[0023] Figure 6 This is a schematic diagram of the pre-sealed structure of the soft-pack battery gas bag according to Embodiment 5 of the present invention.

[0024] Figure 7 This is a schematic diagram of the first and second reserved positions in the production method of the prefabricated sealing structure of the soft-pack battery air bag according to Embodiment 1 of the present invention.

[0025] In the figure, 100 is the air bag; 110 is the receiving cavity; 111 is the cell cavity; 112 is the liquid replenishment cavity; 120 is the casing part; 200 is the separator; 210 is the reinforcement part; 220 is the weak part; 230 is the leak-proof part; 300 is the liquid replenishment sealing strip; 410 is the first reserved position; and 420 is the second reserved position. Detailed Implementation

[0026] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0027] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0028] Furthermore, in this invention, descriptions involving terms such as "first," "second," and "a" are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0031] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0032] Example 1 like Figure 1 , Figure 2 As shown, a pre-sealed structure for a soft-pack battery air bag includes: The air bag 100 has a receiving cavity 110; A separating band 200 is located in the air bag 100. The separating band 200 includes a reinforcing part 210 and a weak part 220. The weak part 220 is located in the gap between two adjacent reinforcing parts 210 and connects two adjacent reinforcing parts 210. The reinforcing parts 210 and the weak part 220 together divide the receiving cavity 110 into a cell cavity 111 and a liquid replenishment cavity 112. The mechanical strength of the weak part 220 is lower than that of the reinforcing part 210. When an opening force is applied, the weak part 220 will rupture preferentially over the reinforcing part 210. When the weak part 220 breaks, the cell cavity 111 is connected to the electrolyte replenishment cavity 112, so that the electrolyte in the electrolyte replenishment cavity 112 flows into the cell cavity 111.

[0033] In this embodiment, by forming a partition strip 200 consisting of a reinforcing part 210 and a weak part 220 inside the air bag 100, the receiving cavity 110 is pre-divided into a cell cavity 111 and a replenishment cavity 112. Taking advantage of the fact that the mechanical strength of the weak part 220 is lower than that of the reinforcing part 210, the weak part 220 is preferentially and controllably ruptured when an opening force is applied (by means of external force such as squeezing), so as to achieve a one-time complete release of electrolyte from the replenishment cavity 112 to the cell cavity 111. This structure avoids additional dismantling tools or complex triggering mechanisms, simplifies the secondary liquid injection activation operation, and ensures that the reinforcing part 210 maintains its sealing integrity during use to prevent electrolyte leakage.

[0034] In this embodiment, the liquid replenishment chamber 112 is located in the middle of the side of the air bag 100 away from the cell chamber 111.

[0035] The replenishing chamber 112 has an opening on the side away from the cell cavity 111, and electrolyte is injected into the replenishing chamber 112 through the opening during secondary electrolyte injection.

[0036] Furthermore, it also includes a liquid replenishment sealing strip 300, which is located in the air bag 100. The liquid replenishment cavity 112 is located in the middle of the air bag 100 on the side away from the cell cavity 111. The reinforcing part 210, the weak part 220 and the liquid replenishment sealing strip 300 surround and form the liquid replenishment cavity 112. When the secondary liquid injection is completed, the opening of the liquid replenishment cavity 112 is sealed by the liquid replenishment sealing strip 300.

[0037] It is worth noting that the liquid sealing tape 300 is formed by heat sealing or other processing methods, ensuring that its mechanical strength is higher than that of the weak part 220.

[0038] In this embodiment, a liquid replenishment sealing strip 300 is introduced, which together with the reinforcing part 210 and the weak part 220 forms a closed liquid replenishment cavity 112, providing an independent and reliable storage space for the secondary electrolyte. This structure ensures the openness of the liquid replenishment cavity 112 before liquid injection, and can also achieve final sealing through the liquid replenishment sealing strip 300, taking into account both process convenience and long-term storage sealing.

[0039] Furthermore, the end of the reinforcing part 210 partially overlaps with the end of the weak part 220 to form a leak-proof part 230.

[0040] In this embodiment, the leak-proof part 230 refers to the end of the weak part 220 extending beyond itself and reaching the original end of the reinforcing part 210 when it is formed, thereby eliminating the gap between the reinforcing part 210 and the weak part 220, effectively preventing electrolyte from leaking from the gap between the reinforcing part 210 and the weak part 220, and significantly improving the reliability and leak-proof performance of the sealing structure.

[0041] Furthermore, the reinforcing part 210 is the heat-sealed area formed by the air bag 100 during the heat-sealing process.

[0042] In this embodiment, the reinforcing part 210 is set as the heat-sealing area formed by heat sealing. The mature and efficient heat sealing process is used to achieve a seal with high mechanical strength and high airtightness, ensuring that the cell cavity 111 remains stably isolated throughout the entire battery life cycle, thereby improving battery safety and cycle life.

[0043] As one alternative, the air bag 100 can be ultrasonically welded to replace the original heat-sealed position to form the reinforced part 210. However, the mechanical strength of the reinforced part 210 formed by ultrasonic welding needs to be much higher than that of the weak part 220 formed by ultrasonic welding.

[0044] It is worth noting that the mechanical strength of the weld can be controlled by adjusting parameters such as amplitude, energy, power, and time of the ultrasonic welding machine, thereby ensuring that the mechanical strength of the reinforced part 210 formed by ultrasonic welding is higher than that of the weak part 220 formed by ultrasonic welding.

[0045] Furthermore, the weak part 220 is the ultrasonic welding area formed by the air bag 100 during the ultrasonic welding process.

[0046] It is worth noting that the weak part 220 can be designed into different shapes (square, trapezoid, V-shape, etc.) as needed, and the ultrasonic encapsulation thickness can be adjusted according to the thickness of the aluminum-plastic film and the extrusion pressure requirements.

[0047] In addition, the weak part 220 is welded using an ultrasonic welding machine with a toothless or shallow tooth welding head and welding seat. The thickness and mechanical strength of the weak part 220 are controlled by adjusting the parameters of the ultrasonic welding machine to match the extrusion pressure. The inner CPP material of the two aluminum-plastic film layers of the weak part 220 is not completely melted and bonded, making it a weak point in the pre-sealed structure of the soft-pack battery air bag.

[0048] In this embodiment, the weak part 220 is set as the ultrasonic welding area. By precisely controlling the ultrasonic welding parameters, a weak connection area with mechanical strength lower than that of the heat-sealed reinforced part 210 is formed. This method requires no additional materials, has strong process compatibility, and can precisely control the rupture threshold to achieve reliable and consistent opening performance.

[0049] Example 2 like Figure 3 As shown, the other structures in this embodiment are the same as in Embodiment 1. The difference is that the air bag 100 is also provided with a shell-punching section 120. The shell-punching section 120 is the shell-punching area formed by the air bag 100 during the shell-punching process. The shell-punching section 120 is located in the liquid replenishment chamber 112.

[0050] It is worth noting that the stamping process refers to the process of using a mold to stamp on the air bag 100 to form a recessed area of ​​a predetermined shape. Its main function is to increase the volume of the corresponding local area of ​​the air bag 100, thereby accommodating the electrolyte required for liquid injection.

[0051] In this embodiment, the amount of secondary electrolyte injected determines whether it is necessary to punch a shell 100 at the position of the replenishment chamber 112 to form a punched shell part 120. The length, width, and depth of the punched shell part 120 are determined according to the amount of secondary electrolyte injected. The punched shell part 120 is formed by punching a punching mold, and the punching depth can be adjusted by punching parameters.

[0052] Example 3 like Figure 4 As shown, the other structures of this embodiment are the same as those of Embodiment 1. The difference is that the liquid replenishment chamber 112 is located on the left side of the air bag 100, and the liquid replenishment chamber 112 is formed by the reinforcement part 210, the weak part 220, the liquid replenishment sealing strip 300 and the edge of the air bag 100.

[0053] Furthermore, the air bag 100 is also provided with a shell-punching section 120, which is a shell-punching area formed by the air bag 100 during the shell-punching process, and the shell-punching section 120 is located in the liquid replenishment chamber 112.

[0054] Example 4 like Figure 5 As shown, the other structures of this embodiment are the same as those of Embodiment 1. The difference is that the liquid replenishment chamber 112 is located on the right side of the air bag 100, and the liquid replenishment chamber 112 is formed by the reinforcement part 210, the weak part 220, the liquid replenishment sealing strip 300 and the edge of the air bag 100.

[0055] Furthermore, the air bag 100 is also provided with a shell-punching section 120, which is a shell-punching area formed by the air bag 100 during the shell-punching process, and the shell-punching section 120 is located in the liquid replenishment chamber 112.

[0056] Example 5 like Figure 6 As shown, the other structures of this embodiment are the same as those of Embodiment 1. The difference is that there are two liquid replenishment chambers 112. The two liquid replenishment chambers 112 are located on the left and right sides of the air bag 100, respectively. The reinforcing part 210, the weak part 220, the liquid replenishment sealing strip 300 and the edge of the air bag 100 surround and form the liquid replenishment chamber 112.

[0057] Furthermore, the air bag 100 is also provided with a shell-punching section 120, which is a shell-punching area formed by the air bag 100 during the shell-punching process, and the shell-punching section 120 is located in the liquid replenishment chamber 112.

[0058] like Figure 1 , Figure 2 , Figure 7 As shown, a production method applied to a pre-sealed structure for a soft-pack battery gas bag as described in Example 1 includes the following steps: S1: Inject liquid into the air bag 100 once; S2: After one injection is completed, the weak part 220 is formed at the first reserved position 410, so that at most one end of the weak part 220 is connected to the edge of the air bag 100. It is worth noting here that the first reserved position 410 is the pre-processing position of the weak part 220.

[0059] S3: The reinforcing part 210 is formed in the second reserved position 420, so that the end of each of the weak parts 220 that is not connected to the edge of the air bag 100 is connected to the edge of the air bag 100 through the reinforcing part 210, thereby dividing the receiving cavity 110 into the cell cavity 111 and the liquid replenishment cavity 112. It is worth noting that the second reserved position 410 is the pre-processing position of the reinforcing part 210.

[0060] It is worth noting that, since the weak part 220 can be located away from the edge of the air bag 100, or one end of the weak part 220 can be connected to the edge of the air bag 100, the number and position of the reinforcing parts can be divided into two cases: when the weak part 220 is located away from the edge of the air bag 100, there are two reinforcing parts 210, and the two ends of the weak part 220 that are not connected to the edge of the air bag 100 are connected to the edge of the air bag 100 through the two reinforcing parts 210 respectively; when one end of the weak part 220 is connected to the edge of the air bag 100, there is one reinforcing part 210, and the other end of the weak part 220 is connected to the edge of the air bag 100 through the reinforcing part 210.

[0061] S4: Inject secondary electrolyte into the replenishment chamber 112 through the opening of the replenishment chamber 112; S5: Process to form the replenishment sealing strip 300 to close the opening of the replenishment cavity 112.

[0062] It is worth noting that the liquid sealing tape 300 is formed by heat sealing or other processing methods, ensuring that its mechanical strength is higher than that of the weak part 220.

[0063] In this embodiment, a production method matching the pre-fabricated sealing structure is provided. First, the liquid injection and formation are completed, and then the separation structure is constructed and the secondary electrolyte is injected. This avoids the secondary electrolyte from participating in side reactions and being lost during the formation stage. The method has a clear process and reasonable process connection, ensuring that the liquid replenishment chamber 112 is in an open state during liquid injection, and is reliably sealed by the liquid replenishment sealing tape 300 after liquid injection, thereby improving the production yield and product consistency.

[0064] Further, in step S2, the first reserved position 410 of the air bag 100 is ultrasonically welded to form the weak part 220.

[0065] In this embodiment, ultrasonic welding is used in step S2 to form the weak part 220, which can precisely control the mechanical strength of the welded area, thereby differentiating the mechanical strength of the weak part 220 from that of the reinforced part 210. Ultrasonic welding is fast and has a small heat-affected zone, avoiding damage to the base material of the air bag 100 and ensuring the consistency and controllability of the opening force of the weak part 220.

[0066] As one alternative, the air bag 100 is ultrasonically welded to form the reinforced part 210, but the mechanical strength of the reinforced part 210 formed by ultrasonic welding needs to be much higher than that of the weak part 220 formed by ultrasonic welding.

[0067] like Figure 1 , Figure 2 , Figure 7 As shown, based on the above embodiment, in step S3, the second reserved position 420 of the air bag 100 is heat-sealed to form the reinforcing part 210.

[0068] In this embodiment, the reinforced part 210 is formed by heat sealing in step S3, which is compatible with the standard packaging process of soft-pack batteries. No additional processing equipment is required, ensuring the reliability of long-term isolation of the cell cavity 111.

[0069] like Figure 1 , Figure 2 , Figure 7 As shown, based on the above embodiment, in step S3, the first reserved position 410 and the second reserved position 420 partially overlap, so that when the reinforcing part 210 is formed in the second reserved position 420, the end of the reinforcing part 210 partially overlaps with the end of the weak part 220 to form the leak-proof part 230.

[0070] In this embodiment, the first reserved position 410 and the second reserved position 420 partially overlap, so that when the reinforcing part 210 is formed in the second reserved position 420, the leak-proof part 230 is integrally formed without additional processes, effectively preventing electrolyte from leaking from the gap between the reinforcing part 210 and the weak part 220, and significantly improving the reliability and leak-proof performance of the sealing structure.

[0071] like Figures 3 to 6 As shown, a production method is applied to a pre-sealed soft-pack battery gas bag structure as described in Examples 2 to 5, and is carried out in the same manner as in Example 1.

Claims

1. A pre-sealed structure for a soft-pack battery gas bag, characterized in that, include: An air bag, which has a receiving cavity; A separating band is located in the air bag. The separating band includes a reinforcing section and a weak section. The weak section is located in the gap between two adjacent reinforcing sections and connects the two adjacent reinforcing sections, or it is located between the reinforcing section and the edge of the air bag and connects the reinforcing section and the edge of the air bag. The reinforcing section and the weak section together divide the receiving cavity into a cell cavity and a liquid replenishment cavity. The mechanical strength of the weak section is lower than that of the reinforcing section. When an opening force is applied, the weak section breaks first before the reinforcing section. When the weak part breaks, the cell cavity is connected to the electrolyte replenishment cavity, so that the electrolyte in the electrolyte replenishment cavity flows into the cell cavity.

2. The pre-sealed structure for a soft-pack battery air bag according to claim 1, characterized in that: It also includes a liquid replenishment sealing strip, which is located in the air bag. The reinforcing part, the weak part, and the liquid replenishment sealing strip surround to form the liquid replenishment cavity, or the reinforcing part, the weak part, the liquid replenishment sealing strip, and the edge of the air bag surround to form the liquid replenishment cavity.

3. The pre-sealed structure for a soft-pack battery air bag according to claim 1, characterized in that: The end of the reinforced part overlaps with the end of the weak part to form a leak-proof part.

4. The pre-sealed structure for a soft-pack battery air bag according to claim 1, characterized in that: The reinforcing part is the heat-sealed area formed during the heat-sealing process of the air bag.

5. The pre-sealed structure for a soft-pack battery air bag according to claim 1, characterized in that: The weak point is the ultrasonic welding area formed during the ultrasonic welding process of the air bag.

6. The pre-sealed structure for a soft-pack battery air bag according to claim 1, characterized in that: The air bag is also provided with a shell-punching section, which is the shell-punching area formed by the air bag during the shell-punching process, and the shell-punching section is located in the liquid replenishment chamber.

7. A method for producing a pre-sealed structure for a soft-pack battery bag, characterized in that, The method applied to the pre-sealing structure of a soft-pack battery air bag according to any one of claims 2-6 includes the following steps: S1: Inject liquid into the air bag once; S2: After one injection is completed, the weak part is formed at the first reserved position, so that at most one end of the weak part is connected to the edge of the air bag; S3: The reinforcing part is formed at the second reserved position, so that the end of each weak part that is not connected to the edge of the air bag is connected to the edge of the air bag through the reinforcing part, thereby dividing the receiving cavity into the cell cavity and the liquid replenishment cavity; S4: Inject secondary electrolyte into the replenishment chamber through the opening of the replenishment chamber; S5: Process to form the replenishment sealing strip to seal the opening of the replenishment cavity.

8. A method for producing a pre-sealed structure for a soft-pack battery bag according to claim 7, characterized in that: In step S2, the first reserved position of the air bag is ultrasonically welded to form the weak part.

9. A method for producing a pre-sealed structure for a soft-pack battery bag according to claim 7, characterized in that: In step S3, the second reserved position of the air bag is heat-sealed to form the reinforced part.

10. A method for producing a pre-sealed structure for a soft-pack battery bag according to claim 9, characterized in that: In step S3, the first reserved position and the second reserved position partially overlap, so that when the reinforcing part is formed in the second reserved position, the end of the reinforcing part partially overlaps with the end of the weak part, thereby forming a leak-proof part.

Images